Bolt of Keranos

Call down a bolt from the Nyx, seemingly belonging to Keranos himself. Make a ranged spell attack against the target. On a hit, the target takes 2d8 lightning damage. Target makes a dexterity saving throw. On a succeed, target takes half damage. On a fail, target becomes paralyzed and cannot move until attacked again. 

At Higher Level: At level 10 damage is increased by 2d8. At level 15, damage is increased by 2d8 and can have one additional target.